So I haven't actually owned an iphone in about 6months but a friend recently got one and had this problem, and I remember being confused about it when I owned one. Has it always been like this, or are we just unimaginably thick?
– SCdFSep 16 '10 at 7:33

@SCdF - I think it has always been like this but I'm not sure either. My first iPhone was 3GS with iPhone OS 3.
– Jacob GorbanSep 17 '10 at 12:20

@JacobGorban My iPhone 4S has the entry "Add Custom Label" at the bottom of the label-picker screen, below all of my existing custom labels.
– CajunLukeAug 20 '12 at 23:12

When you enter a phone number for the contact, immediately below that number should appear a new place to enter another phone number. You can change the type of phone like work, home, iPhone, blackberry, etc.